Effect of Impingement Density and Nozzle to Target Distance on Spray Cooling of Steel Plate—An Experimental Investigation

Abstract

ABSTRACTIn the steel making industry, high heat fluxes are obtained using effective cooling techniques such as spray impingement cooling. Spray impingement technique involve factors like droplet size, spray height and spray angle, impingement density, and nozzle geometry rendering it very difficult to measure the effects of individual parameters. In the present study, the cooling rate of the plate was experimentally investigated using distilled water as coolant in 3 pressurized nozzles for spray over the surface of the steel plate at elevated temperatures and the behavior of plate temperature with time was tabulated. Cooling curves were generated for different and varying spray parameters like water pressures, nozzle tip to surface distance, and impingement density. It was observed that the cooling rate at the stagnation zone was strongly dependent on the water pressures and nozzle tip to surface distances with maximum cooling rates reaching within 1–2 seconds after the impingement. The average impingement density increased with increase in water pressure and the cooling rate reduces at higher pressures and nozzle tip to surface distances.